1. FIELD OF THE INVENTION
The present invention relates to a device for delivering printed products out of a fan in a folding apparatus to thereafter form a shingled product stream. The device of the present invention has at least one endless chain which is lead around a drive shaft of the fan and individual links of the chain are equally spaced from one another. The chain assists in ensuring gentle handling of the products, to thereby eliminated smearing, and also ensures an accurate and unvarying shingled product stream.
2. DESCRIPTION OF THE PRIOR ART
European Patent No. 0 059 873 shows a device for the delivery of printed products out of fans in a folding apparatus. The device in that patent has several fans arranged side-by-side on an axle. Next to each of the fans there is a disk which is eccentrically located with respect to the axle of the fans. Each disk carries a stop wheel, which is driven by inner gearing having a predetermined transmission ratio. The stop wheels rotate at a lower rotational or circumferential speed than the fans, so that the printed products moving forward and dipping into the fan pockets are decelerated before they reach the pocket bottom. As a result, the length of the fan pockets cannot be utilized in their entirety to reduce the kinetic energy inherent in the printed products.
Since there is a predetermined fixed transmission ratio between the stop wheel and the associated fan in the device described in the above patent, it is not possible to change or adjust the deceleration characteristics. Furthermore, the high manufacturing costs of the gear constructions used in this device are disadvantageous.
The second embodiment disclosed in EPO 0 059 873 uses grippers disposed on the stop wheel in the area of the stops. The grippers firmly grip the front edge of the printed products. The grippers are controlled by roller levers moved by rollers running on a stationary cam. This design requires a disproportionately high investment in mechanical equipment to implement.
In European Patent No. 0 164 440 there is disclosed a rotary delivery device for receiving newspapers at high speeds. On a central hub of the delivery device there are arranged several accurate delivery fingers which form individual pockets, into which the newspapers to be delivered enter. Close to the bottom of the pockets there are disposed spring-biased clamping bars which are pressed back by the back of a newspaper entering the pocket. Because the clamping bars are spring-biased, the back of the newspaper is clamped between the clamping bar and an adjacent delivery finger.
In the case of newspapers consisting of multiple layers, the ink absorptivity is influenced by the porous quality of the paper, especially in gravure printing. As a result, newspaper products, which are frequently printed with only one color, are relatively insensitive to smudging.
In offset printing, however, the printing material is frequently printed on both sides. Furthermore, multiple layers of ink are often applied, and the uppermost layer may not be completely cured or dried after the printed material has passed through a dryer. The printed image on such products is prone to smudging as the result of use of the clamping bars described in EPO 0 164 440. Therefore, the mechanical strain exerted on the products by this device is not favorable, and its use for the delivery of products produced in offset printing is not desirable.
European Patent No. 0 307 889 also discloses a device for the delivery of printed products out of fans from a folding apparatus. In that patent, at least one cam segment is arranged in a manner such that a chain can be lead around the drive shaft of the fan. On the chain there are arranged, at equal distances, angle and clamping pieces which can be brought into working contact with the fan blades. In this device, the products entering the fan pockets first are gripped by the angle pieces fastened to the chain, and aligned. The clamping piece acting on the products from above press the products onto the fan blade on which the products lie. Thus, the products are pressed onto the fan wheel blades during their movement out of the fan pockets. As a result, the underside of the products can be smudged or scratched, despite a teflon coating on the inside of the fan blade.